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141.
PURPOSE: The clinical significance and prognostic value of the histopathologic parameters used in both the Dukes and Jass classifications were evaluated to select those with an independent effect on survival after radical surgery for colorectal cancer. METHODS: The depth of local spread (limited to the bowel wall or extended beyond it), the number of metastatic lymph nodes (none, 1–4, more than 4), the character of the invasive margin (pushing or infiltrating), and the presence or absence of conspicuous peritumoral lymphocytic infiltration were assessed in 235 patients who had undergone radical resection for colorectal cancer. The influence of these variables on survival was studied by univariate and multivariate analysis. RESULTS: No significant difference in survival was found between patients with conspicuous peritumoral infiltrate and those without it; moreover, multivariate analysis failed to show any independent prognostic value for either lymphocytic infiltration or depth of local invasion. However, the character of the invasive margin and the number of metastatic lymph nodes were identified as the only variables with any independent importance on survival. Based on these data, a new prognostic model may be proposed; it uses the character of the infiltrative margin as a discriminating factor among patients within the lymph node-negative (Dukes A and B stages) and lymph node-positive (Dukes C1 and C2 subsets) groups. A good prognosis for Dukes A, B, and C1 patients was associated with pushing tumors; C1 and C2 patients with infiltrating tumors had a poor prognosis. On the whole, the new prognostic model has allowed for the placement of 59.6 percent of our patients into groups that provide a confident prognosis. The clinical outcome of Dukes A and B patients with infiltrating tumors is still uncertain. CONCLUSIONS: The character of the invasive margin is an important prognostic factor in colorectal cancer. The association of this parameter with the traditional Dukes classification may provide additional useful prognostic information and aid in the selection of those patients who could most benefit from adjuvant therapy.  相似文献   
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Background  

In the past, sporadic demonstrations of the existence of a subarachnoid subdiaphragmatic cistern have been published. The aim of this study was to evaluate the anatomical characteristics of the subdiaphragmatic cistern of the pituitary gland.  相似文献   
144.
BACKGROUND: Transplanting pancreatic islets is of significant interest for type 1 diabetes mellitus. After intraportal injection of islets, inferior engraftment and eventual loss of transplanted islets constitute major limitations. Therefore, alternative approaches will be helpful. Here, we evaluated in animals whether an isolated venous sac would support survival of transplanted islets, along with correction of hyperglycemia. METHODS: Pancreatic islets isolated from adult Lewis rats were transplanted either into an isolated venous sac made from lumbar vein or into the portal vein of syngeneic rats. The integrity and vascular organization of the venous sac was determined by studies of the local microcirculation. The engraftment, survival, and function of transplanted islets were analyzed by histology, including endocrine function in situ and by glycemic control in rats with streptozotocin-induced diabetes. RESULTS: Transplanted islets showed normal morphology with insulin expression in isolated venous sac during the long term. Transplanted islets received blood supply from vasa vasorum and had access to drainage through venous tributaries in the venous sac. This resulted in restoration of euglycemia in diabetic rats. Removal of islet graft-bearing venous sac in diabetic rats led to recurrence of hyperglycemia. By contrast, euglycemia was not restored in rats treated by intraportal transplantation of islets. CONCLUSIONS: We demonstrated that pancreatic islets successfully engrafted and functioned in the isolated venous sac with ability to restore euglycemia in diabetic rats. Therefore, the isolated venous sac offers a new site for transplantation of pancreatic islets. This would be clinically beneficial as an alternative to intrahepatic islet transplantation.  相似文献   
145.

Background

Elderly patients with metastatic renal cell carcinoma (mRCC) may require special treatment considerations, particularly when comorbidities are present. An understanding of the efficacy and safety of targeted agents in elderly patients with mRCC is essential to provide individualized therapy.

Objective

To evaluate the efficacy and safety of everolimus in elderly patients (those ≥65 and ≥70 yr of age) enrolled in RECORD-1.

Design, setting, and participants

The multicenter randomized RECORD-1 phase 3 trial (Clinicaltrials.gov identifier, NCT00410124; http://www.clinicaltrials.gov) enrolled patients with mRCC who progressed during or within 6 mo of stopping sunitinib and/or sorafenib treatment (n = 416).

Intervention

Everolimus 10 mg once daily (n = 277) or placebo (n = 139) plus best supportive care. Treatment was continued until disease progression or unacceptable toxicity.

Measurements

Median progression-free survival (PFS), median overall survival (OS), and time to deterioration in Karnofsky performance status (TTD-KPS) were assessed using the Kaplan-Meier method; the log-rank test was used to compare treatment arms. Other outcomes evaluated included reduction in tumor burden, overall response rate (ORR), and safety.

Results and limitations

In RECORD-1, 36.8% of patients were ≥65 yr and 17.5% were ≥70 yr of age. PFS, OS, TTD-KPS, reduction in tumor burden, and ORR were similar in the elderly and the overall RECORD-1 population. Everolimus was generally well tolerated in elderly patients, and most adverse events were grade 1 or 2 in severity. The toxicity profile of everolimus was generally similar in older patients and the overall population; however, peripheral edema, cough, rash, and diarrhea were reported more frequently in the elderly regardless of treatment. The retrospective nature of the analyses was the major limitation.

Conclusions

Everolimus is effective and tolerable in elderly patients with mRCC. When selecting targeted therapies in these patients, the specific toxicity profile of each agent and any patient comorbidities should be considered.  相似文献   
146.
Patients with autoimmune rheumatic disorders have an increased incidence of cardiovascular (CV) events and mortality. Despite this being related to a high prevalence of the traditional CV risk factors, systemic inflammation has been postulated to be an independent CV risk factor, particularly in patients with rheumatoid arthritis (RA). However, data are still controversial. We designed a case–control study, in which patients with autoimmune rheumatic disorders were matched with age-, sex-matched controls. Prevalence of early atherosclerosis was assessed by carotid artery intima-media thickness (IMT) measurement. IMT values were considered normal (IMT ≤ 0.9 mm) or abnormal (IMT > 0.9). Multivariate analysis was performed to identify predictors of pathological IMT. Overall, 152 patients and 140 matched controls were enrolled. Prevalence of >0.9 mm IMT values did not significantly differ between patients with autoimmune rheumatic disorders and controls (61 vs. 69%, p = 0.1). In detail, a similar IMT distribution between the 69 RA patients and controls was observed. Cases with a CV risk factor showed a higher prevalence of pathological IMT as compared to those without any risk factor, both in patients (77.1 vs. 38.6%; p < 0.0001) and controls (84.6 vs. 25%; p < 0.0001). At multivariate analysis, age and presence of CV risk factors were found to be independent predictors of >0.9 mm IMT, while RA as well as any other considered rheumatic disease were not. Our data found a similar prevalence of preclinical arterial wall atherosclerotic damage in patients with autoimmune rheumatic diseases and matched controls. Presence of traditional CV risk factors and patient age remain the main factors involved in preclinical atherosclerosis in patients with autoimmune rheumatic disorders, including RA.  相似文献   
147.
148.
The aim of this study is to chart the hypoxic ventilatory decline experienced by climbers exposed to hypoxic stimulus with and without 7 days of acclimatisation to intermittent altitude increases of 4400 to 6960 m. Our results revealed that hypoxic ventilatory depression was present during day 1 of hypoxia and decreased thereafter, returning to control values by day 7. These results indicate that the hypoxic ventilatory response, which is mediated by carotid body chemoreceptors, depends on the pattern and intensity of hypoxia exposure. Chronic intermittent hypoxia could facilitate this recovery, yielding faster returns to ventilatory baseline levels.  相似文献   
149.
150.
The chemistry of the catalyst-cocatalyst interaction was investigated in systems containing different internal/external donor pairs. Qualitatively similar results were obtained with the ethyl benzoate/methyl p-toluate (EB/MPT) and dibutyl phthalate/triethoxy(phenyl)silane (DBP/EPS) systems, which thus were assumed to follow the same model. Quantitative differences were accounted for by assuming a different basic strength of the two donor pairs towards MgCl2 and AlEt3.  相似文献   
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